Genetic variability and phylogeny analysis of partial L1 gene of human papillomavirus variants in Buenos Aires, Argentina.

In the present study, the molecular characterization of HPV variants 16, 18, 31, 58, 6 and 11 within the MY06/MY11 L1 genomic region was performed in 128 sequences. For HPV 16, all of the sequences analyzed had a 3 nucleotide insertion resulting in the insertion of serine in the L1 protein sequence; and 4 sequences had at least one single nucleotide polymorphism (SNP). Twelve base substitutions were detected in HPV 58, 6 SNPs produced amino acid changes, and the other SNPs detected were found to be silent mutations. For HPV 31, 25 SNPs were detected as silent mutations. Of the 8 SNPs detected on HPV 18, three produced amino acid changes, the remaining SNPs detected were silent mutations. For HPV 6, 10 SNPs were detected and none of them produced amino acid changes. From the 16 sequences analyzed for HPV 11, two SNPs were detected and neither of them produced amino acid substitutions. Phylogenetic trees were constructed for HPV 16, HPV 18, HPV 31, HPV 58, HPV 6 and HPV 11. In the current study 8 new variants were identified based on sequencing of the L1 region. Changes in the L1 region of the HPV genome may be important for discriminating the infectious potential of different variants, as well as in defining epitopes relevant to vaccine design. The findings of this study indicate that there are new variants of HPV circulating in Argentina, which need to be confirmed by further analyses of the complete HPV genome.

How common is delayed cyclosporine absorption following liver transplantation?

The mean time to peak absorption of cyclosporine (CsA) in liver transplant patients is approximately 2 hours, but in some patients the peak occurs later. The goal of this study was, therefore, to investigate the incidence of delayed absorption in 27 de novo liver transplant recipients receiving CsA > or =10 mg/kg/day (C(2) monitoring) and in 15 maintenance patients. Patients were categorized as 'normal' absorbers (C(2) exceeding C(4) and C(6)) or 'delayed' absorbers (C(4) or C(6) exceeding C(2)), and as 'good' (>800 ng/mL at C(0), C(2), C(4), or C(6)) or 'poor' absorbers (C(0), C(2), C(4) and C(6) <800 ng/mL) on the day of study. Among de novo patients, 15 (56%) had 'normal' CsA absorption and 12 (44%) 'delayed' absorption. Good CsA absorption occurred in 16 patients (59%) and poor absorption in 11 (41%). The proportion of poor absorbers was similar in patients with normal (6/15, 40%) or delayed (5/12, 42%) absorption. Among the 12 delayed absorbers, 11 had peak CsA concentration at C(4). Mean C(0) level was significantly higher in delayed absorbers (282 +/- 96 ng/mL) than in normal absorbers (185 +/- 88 ng/mL; P = .01). Delayed absorbers reverted to normal absorption (C(2) > C(4)) after a median of 6 days from the day of study, and no cases of delayed absorption were found among maintenance patients. In conclusion, almost 50% of the patients had delayed CsA absorption early posttransplant; around half of these exhibited normal CsA exposure. Measurement of C(4) in addition to C(2) differentiates effectively between delayed and poor absorbers of CsA such that over- or underimmunosuppression can be avoided.

Evaluation of HTLV-I/II infection in blood donors in Buenos Aires

HTLV-I and HTLV-II are two related retroviruses that are transmitted by sexual contact, breast feeding, blood transfusion and needle sharing. In this study the prevalence of HTLV-I and HTLV-II was evaluated in voluntary blood donors as a measure of the infection in the general population. Samples were tested by a gelatine particle agglutination test and repeatedly reactive samples were confirmed by Western blot tests (WBT), enriched with recombinant rgp21, rgp46I y rgp46II proteins, which differentiates HTLV-I and HTLV-II antibodies. Of 19,426 samples, 40 were repeatedly reactive by particle agglutination (0.21 percent). When analyzed by WBT, 6 met the criteria for HTLV-I (0.036 percent), 2 for HTLV-II (0.01 percent) and 1 for HTLV-I/II, 13 samples were indeterminate and 18 were negative. The prevalence is low and comparable to that from non endemic countries. Screening for anti HTLV-I/II antibodies is necessary to prevent transmission through blood transfusions.(AU)

Evaluation of HTLV-I/II infection in blood donors in Buenos Aires

HTLV-I and HTLV-II are two related retroviruses that are transmitted by sexual contact, breast feeding, blood transfusion and needle sharing. In this study the prevalence of HTLV-I and HTLV-II was evaluated in voluntary blood donors as a measure of the infection in the general population. Samples were tested by a gelatine particle agglutination test and repeatedly reactive samples were confirmed by Western blot tests (WBT), enriched with recombinant rgp21, rgp46I y rgp46II proteins, which differentiates HTLV-I and HTLV-II antibodies. Of 19,426 samples, 40 were repeatedly reactive by particle agglutination (0.21 percent). When analyzed by WBT, 6 met the criteria for HTLV-I (0.036 percent), 2 for HTLV-II (0.01 percent) and 1 for HTLV-I/II, 13 samples were indeterminate and 18 were negative. The prevalence is low and comparable to that from non endemic countries. Screening for anti HTLV-I/II antibodies is necessary to prevent transmission through blood transfusions.